Added many missing *Pxxx types.
Removed a few *LPxxx types that are not supposed to be there (in
particular LPICONINFO).
Added a few missing *LPCxxx types (MENUITEMINFO, SCROLLINFO,
DLGITEMTEMPLATE).
WINHELP and PE_ACCEL are internal types.
MULTIKEYHELP and HELPWININFO both have an A and W variant.
NUMBERFMT, CURRENCYFMT and the related API belong to winnls.h.
Added missing ARW_xxx defines (for sysmetrics).

diff --git a/windows/winhelp.c b/windows/winhelp.c
index 9e3ca16..f664221 100644
--- a/windows/winhelp.c
+++ b/windows/winhelp.c
@@ -18,6 +18,17 @@
 DEFAULT_DEBUG_CHANNEL(win);
 
 
+/* WinHelp internal structure */
+typedef struct
+{
+    WORD size;
+    WORD command;
+    LONG data;
+    LONG reserved;
+    WORD ofsFilename;
+    WORD ofsData;
+} WINHELP,*LPWINHELP;
+
 /**********************************************************************
  *             WinHelp16   (USER.171)
  */
@@ -89,10 +100,10 @@
 			dsize = dwData ? strlen( (LPSTR)dwData )+1: 0;
 			break;
 		case HELP_MULTIKEY:
-			dsize = ((LPMULTIKEYHELP)dwData)->mkSize;
+			dsize = ((LPMULTIKEYHELPA)dwData)->mkSize;
 			break;
 		case HELP_SETWINPOS:
-			dsize = ((LPHELPWININFO)dwData)->wStructSize;
+			dsize = ((LPHELPWININFOA)dwData)->wStructSize;
 			break;
 		default:
 			WARN("Unknown help command %d\n",wCommand);